HANOVER, Germany (Jan. 10)—Bernd Frangenberg, president and CEO of Continental Tire North America Inc., will retire at the end of March after six years at the helm of the U.S. company. Parent Continental A.G. named Ulrich Wellen, most recently head of original equipment car tire sales, as Frangenberg's successor. He takes over the president's duties immediately, Conti said. Additionally, Continental Tire North America's activities will be more directly controlled by Continental A.G., with Manfred Wennemer and Hans-Joachim Nikolin, heads of the passenger and commercial vehicle tire divisions, respectively, assuming global responsibility for their businesses. Wennemer also is chairman of Conti. Frangenberg, 61, joined Continental in 1981, was given control over North American activities in 1995, and was made a board member in 1998.